This invention involves supports for variably positionable platforms which are adapted to hold books or electronic displays for convenient viewing by a user.
U.S. Pat. No. 7,040,591 by the present inventor incorporated herein by reference describes and claims a swing arm support for books. The platform can be swung to various positions to hold a book so that the user can conveniently read the same while seated, lying in bed, etc.
An important consideration is how the swing arm assembly is held, and co-pending U.S. application Ser. No. 13/629,941 filed Sep. 28, 2012 describes a particular clamping attachment for an upright swing arm support for securing the same to end tables, etc. incorporated herein by reference.
Another important consideration is the ability to easily and precisely adjust the position of the platform so as to present a book or electronic devices perpendicular to the user's line of vision, and to securely maintain any adjusted position.
While the prior book holders have provided for an adjustable positioning of a platform, there are limitations in the adjustments possible and difficulties in quickly establishing a precise desired positioning of the supported article including being able to keep the book or electronic display perpendicular.
It is an object of the present invention to provide a book or electronic device holder which can easily and precisely establish a desired position of a platform which will be securely maintained once adjusted.